As modern technologies advance, diseases of civilization become popular increasingly. The cancer is one of the diseases of civilization. In daily lives, people may contact as many as 17 kinds of chemicals that increase the probability of suffering from cancers. The exhaust generated by diesel and petroleum automobiles, secondhand smoke, and scorched food contain the carcinogens benzene and butadiene. Fire retardants in plastics and paint, anti-dust fabrics, and cleaning solvent also contain carcinogenic chemicals.
Among the cancers as described above, the breast cancer is the most common cancer for females. There are approximately 500 thousand people died of breast cancer worldwide. According to the medical statistic report of Taiwan in 2003, it is found that the breast cancer was the fourth of the death rate of female cancers. The age of occurring breast cancer is around 40 to 50 years old for eastern females and 30 to 40 years old for western ones. The breast cancer is a cancer easily found in the early stage. If tumors are found in the breast, people are normally bashful to tell others. With the fear of breast resection, the opportunity of cure is delayed. In fact, most tumors are benign; treating breast cancer does not necessarily mean losing the whole breast. It is found from recent clinical treatment that the average 10-year survival rate for breast cancer reaches 60%; the survival rate after treatment for the first-stage breast cancer reaches 80%; the survival rate after treatment for the zero-stage breast cancer even approaches 100%. Accordingly, it is extremely important to find and cure early.
There are many ways to prevent breast cancer. In addition to self-examination, there are still breast photography and palpation by physicians. The best method is to do routine examination on items related to breast cancer in hospitals. Most of current hospitals adopt optical tomography scanning and imaging systems to scan breasts and produce breast images. An optical tomography scanning and imaging system scans breasts by using a plurality of optical channel modules. Nonetheless, the distance between the plurality of optical channel modules and breasts is fixed. If the examinee's breasts are smaller, the distance between the plurality of optical channel modules and breasts is greater; if the examinee's breasts are larger, the distance between the plurality of optical channel modules and breasts is smaller. Either the distance greater or smaller, the examination result is influence and leading to reduction in the accuracy of examination. The main cause is that the distance between the plurality of optical channel modules and breasts is not adjustable. In the above examination, the breast examination is taken as an example. An optical tomography scanning and imaging system can be applied to the examination of other body parts. Then the problem described above also occurs.